With the dissemination of silver halide photographic materials in recent years, a powerful demand has arisen for silver halide color photographic materials which have excellent color reproduction and image storage properties when compared with other image forming systems.
The method of colored image formation most generally used in silver halide color photographic materials is that in which the exposed silver halide functions as an oxidizing agent, the oxidized aromatic primary-amine based color developing agent reacts with couplers, and indophenol, indoaniline, indamine, azomethine, phenoxazine or phenazine-based dyes or corresponding dyes are formed. In such a system, the method of reproducing a colored image by means of the subtractive color method is used and, in general, the colored image is formed by varying the amounts of dyes of the three colors yellow, magenta and cyan which are formed.
The 5-pyrazolone azomethine-type magenta couplers and pyrazoloazole-type couplers are known as magenta couplers in such systems. Brilliant dyes with little subsidiary absorbance are needed to obtain color photographic images which have good color reproduction and, in particular, the dyes obtained from the pyrazoloazole type magenta couplers disclosed in U.S. Pat. Nos. 3,061,432 and 4,500,630, for example, are more effective as dyes which are obtained from magenta couplers than the 5-pyrazolone azomethine dyes which have subsidiary absorbance in the 400-450 nm region.
However, the light fastness may be adversely affected when these pyrazoloazole-based magenta couplers are used in a silver halide color photographic material, and there is a problem in that magenta colored staining occurs on prolonged storage after development processing.
When such staining occurs, the quality of the photographic image is markedly reduced, and thus various attempts at improvement have been made.
It has been reported in European Patent EP 0,298,321 that the conjoint use of anti-fading agents which have a specified structure and anti-color staining agents provides some improvement with respect to the above-mentioned problem. Here, the anti-color staining agent is a compound which bonds chemically with the aromatic amine-based developing agent or the oxidized form of the aromatic amine-based developing agent which remains in the photographic material after development processing and produces essentially colorless products. Moreover, in JP-A-3-48845 (corresponding to U.S. Pat. No. 5,212,055), it is indicated that light fading in all regions from the high density parts to the low density parts of the magenta image is improved by using a combination of anti-fading agents of a number of types. (The term "JP-A" as used herein signifies an "unexamined published Japanese patent application".)
It is possible to improve the storage properties of the magenta dye image by using these techniques, but it has not been possible to eliminate completely the occurrence of color staining with the above-mentioned pyrazoloazole-based magenta couplers, and further improvement is desirable.